Pain Under The Left Armpit: 12 Causes Explained

Pain in the armpits can be one of the toughest to bear. Let’s explore the reasons your armpits, the left one specifically, can hurt and what it could mean.

1. Fungal Infection

This is an infection that mostly farmers pick up from handling vegetation. It starts from a scrape or a cut which causes an infection and gives rise to a small nodule, often purple in color. Initially it is tender but it can go on to become an ulcer. If not treated, it could spread to other parts of the body as well.

2. Swollen Lymph Nodes

Our body has many lymph nodes. These are small organs that contain immune cells and help fight infections that our body encounters. These nodes are found throughout the body, including the armpits. A viral infection can sometimes trigger the lymph nodes to release immune cells causing an inflammation of the lymph nodes, which can cause them to become tender to the touch. Painkillers and warm compresses can be used to manage the pain.

3. Muscle Strain

Sports injuries or injuries while lifting heavy weights can sometimes result in pain in the left armpit. This usually happens when muscles like the pectoralis muscle for instance, get injured due to an injury to the chest or arm. Inflammation or a muscle strain can lead to pain in the connected armpit.

4. Angina

Sometimes a reduced flow of blood to the heart muscles causes chest pain. This is known as angina. Angina happens to be one of the symptoms of coronary heart disease. Apart from pain in the left armpit, a few other symptoms of this illness include, shortness of breath, nausea and dizziness.

5. Breast Cancer

Pain in the left armpit can sometimes be caused by breast cancer. In addition to this pain, other symptoms experienced include a lump in the breast that changes in size, flaking around the nipple, an inverted nipple or pitting of the skin.

6. Heartburn

Heartburn can sometimes manifest as pain under the left armpit. In this condition, one experiences a burning sensation in the chest. This happens when the acids in the stomach come back to the esophagus (also known as acid reflux).

7. Contact Dermatitis

Sometimes, shaving or waxing the underarms can irritate the skin. Also, deodorants, and some detergents can cause an allergic reaction causing a rash. These are usually minor and manageable conditions of the skin.

8. Shingles

This is a viral infection that causes blisters to appear on the skin, as a single stripe. When it occurs near the armpit, it can be quite painful. Other symptoms include a fever, fatigue, headaches and even light sensitivity.

9. Anxiety

Excessive stress and anxiety can sometimes cause symptoms such as shaking, irritation and even tachycardia. The increase in heart rate can cause a pain in the left armpit.

10. Peripheral Artery Disease

Sometimes armpit pain could point to peripheral artery disease, which is characterized by narrowing of the arteries of the arms and legs, which decreases the blood supply to the limbs. This happens because of deposition of plaque in the arterial walls. A family history of the disease, obesity, diabetes, hypertension, can increase the risk of this illness.

11. Glandular Infection

12. Breast Infection

Sometimes a breast infection can lead to pain in the armpits. It is accompanied by redness, swelling and even fluid drainage. The lymph nodes may also get enlarged in this condition.

When Does It Warrant A Visit To The Doctor?

Pain in the left armpit, in most cases isn’t caused by anything serious. However, it’s better to err on the side of caution and seek medical help when you notice any of the following symptoms along with the pain in the armpit.

1. There’s a lump in the area which hurts and is changing in size
2. There is sudden and intense pain in the area
3. You have trouble breathing
4. You experience tightness in the chest
5. You have chest pain radiating to the left armpit

In such cases, it is important to reach out to your doctor without delay and have serious medical conditions ruled out.

Disclaimer: The content is purely informative and educational in nature and should not be construed as medical advice. Please use the content only in consultation with an appropriate certified medical or healthcare professional.